JP2011096502A - Vacuum valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum valve having a bellows machine open-close lifetime usable not only in high pressure environment but also in high voltage without large-sizing of the vacuum valve. <P>SOLUTION: In the vacuum valve mounted on a vacuum breaker and a vacuum open-close equipment assembled in a tank filled with an insulating gas, internal pressure type bellows are doubled, a cylindrical shock absorber having both deformation property and cushion property represented by a sponge is sealed in between those bellows, the inner diameter of the shock absorber is made a mountain diameter or less of an insulation side bellows, the outer diameter of the shock absorber is made a valley diameter or more of a vacuum side bellows, the end plate is fixed and adhered to a flange side of a vacuum container movable side in an insulating gas side bellows, and the space between the bellows is made an airtight space by its end plate being joined with the movable side flange. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vacuum valve constituting an arc extinguishing chamber of a vacuum circuit breaker that opens and closes an electric circuit, and more particularly to a vacuum valve disposed in a container filled with an insulating gas.

  The configuration of a conventional vacuum valve is shown in FIG. In the vacuum valve 100, electrodes 5 and 6 for opening and closing a current are fixed to the electrode rods 2 and 7 in a vacuum-tight container, and the movable electrode 6 and the electrode rod for supporting the electrode are supported while maintaining the vacuum-tightness inside the container. A bellows 22 that can be expanded and contracted is provided so that the electrode 7 can be slid in the direction in which the electrodes 5 and 6 come in contact with and away from each other. The bellows 22 uses an internal pressure type bellows in which the pressure on the inner diameter side is generally higher than the pressure on the outer diameter side so that the bellows 22 can be accommodated compactly in the vacuum valve (see, for example, Patent Document 1).

JP-A-60-205926 (Fig. 3)

In order to increase the voltage of the vacuum circuit breaker, a grounding tank (not shown) in which the vacuum valve 100 is housed is filled with an insulating gas such as SF6 gas or dry air, and the withstand voltage performance in the tank and the outer surface of the vacuum valve 100 is There is a gas-insulated vacuum circuit breaker. In this vacuum circuit breaker, since the filled insulating gas is at atmospheric pressure or higher and the pressure difference between the inside and outside of the bellows 22 of the vacuum valve 100 is large, the bellows can be used in a high pressure environment. However, the internal pressure bellows causes a buckling phenomenon if the pressure difference between the internal and external pressures is large, resulting in an upper limit for the working pressure.

There is Patent Document 1 as a prior art document related to the use of a vacuum valve in such a high pressure environment, and the pressure on both sides of the bellows is made by making the bellows a double structure and making the airtight space between the bellows lower than the external pressure. A structure for reducing the difference and extending the mechanical opening / closing life of the bellows under a high pressure environment is disclosed. In the structure of this prior art document, since the bellows are arranged in parallel, it is necessary to secure a sufficient space between the bellows in order to prevent damage due to interference between the bellows, which increases the installation space of the bellows. Along with this, there was a problem that the vacuum valve was enlarged. In addition, when the circuit breaker voltage increases, it is necessary to increase the contact opening speed and increase the opening / closing stroke gap in order to ensure the insulation performance such as the withstand voltage performance and breaking performance of the vacuum valve. Although the required bellows strength is required, an effective measure has not been found for increasing the stress on the bellows due to the increased withstand voltage, which is the purpose of increasing the pressure of the insulating gas.

  The present invention has been made to solve the above-described problems, and is a compact vacuum valve that hardly causes a buckling phenomenon due to a pressure difference between the internal and external pressures even when an internal pressure type bellows is used in a high pressure environment. To get.

A fixed side and a movable side electrode for opening and closing a circuit in the vacuum vessel, an electrode rod that passes through one end of the vacuum vessel to support the movable side electrode and is driven to open and close, and a through-hole of the vacuum vessel in the electrode rod In a vacuum valve comprising an electrode rod and a bellows that is extendable and airtightly connectable between the vacuum vessel, the bellows is an airtight space between a first bellows and a second bellows arranged coaxially in parallel. And the pressure in the airtight space is set to an intermediate value between the pressure on the outer periphery of the first bellows and the pressure on the inner diameter side of the first bellows, and a cushioning material is disposed in the sealed space.

An airtight space is formed between the first bellows and the second bellows, and the pressure in the airtight space is set to an intermediate value between the pressure on the outer periphery of the first bellows and the pressure on the inner diameter side of the first bellows. Since the buffer material is disposed in the sealed space, the difference between the internal and external pressures of the bellows can be reduced, and the bellows can be prevented from buckling. For this reason, a compact vacuum valve can be obtained even if an internal pressure type bellows is used.

It is sectional drawing of the vacuum valve by Embodiment 1 of this invention. It is sectional drawing of the bellows part of FIG. It is sectional drawing of the bellows part of FIG. It is sectional drawing of the vacuum valve by Embodiment 2 of this invention. It is a perspective view of the shock absorbing material of FIG. It is sectional drawing of the vacuum valve which shows Embodiment 3 of this invention. It is sectional drawing of the vacuum valve which shows Embodiment 4 of this invention. It is sectional drawing which shows Embodiment 5 of this invention. It is sectional drawing which shows Embodiment 6 of this invention. It is a figure which shows the structure of the conventional vacuum valve.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a vacuum valve 100 according to the first embodiment. The insulating container 1 and the metal container 4 are combined and both ends are sealed with flanges 3 and 12 to form a vacuum container, and the electrodes 5 and 6 for opening and closing the current are fixed to the electrode rods 2 and 7 in the vacuum container. The movable side electrode 6 and the electrode rod 7 that supports the movable side electrode 6 and the electrode rod 7 that supports the movable side electrode 6 are slidably arranged in a direction in which the electrodes 5 and 6 come in contact with and away from each other while keeping the vacuum airtight inside the container. The movable electrode rod 7 is slidably disposed through the flange 12 at one end of the vacuum vessel, and the electrode rod 7 and the flange 12 are connected by a vacuum side bellows 9 and an insulating gas side bellows 10 to form a vacuum. It is possible to slide while maintaining Between the electrode rod 7 and the flange 12, a vacuum side bellows 9 and an insulating gas side bellows are connected to a connection portion between the vacuum side bellows 9 and the insulating gas side bellows 10 to protect from metal vapor generated when the electrodes 5 and 6 are opened and closed. A bellows protective shield 8 covering the outer periphery of the end portion of 10 is disposed. The bellows has a vacuum side bellows 9 on the outer peripheral side and an insulative gas side bellows 10 on the inner peripheral side thereof. One end of the vacuum side bellows 9 is fixed to the bellows protective shield 8 and the other end is The flange 12 is fixed. One end of the insulating gas side bellows 10 is fixed to the bellows protective shield 8, and the other end is fixed to a disc-shaped end plate 13. A resin guide 14 is inserted into the gap between the insulating gas side bellows 10 and the electrode rod 7 so as to prevent shaft runout during operation of the electrode rod 7.

A buffer material 11 is enclosed in an airtight space 15 formed between the vacuum side bellows 9 and the insulating gas side bellows 10. The cushioning material 11 has a cylindrical shape, and the material thereof is a resin having both deformability and cushioning properties. For example, a foaming molding material such as sponge is used, and the outer diameter of the cushioning material 11 is Is not less than the valley diameter of the vacuum side bellows 9 and the inner diameter of the buffer material 11 is not more than the peak diameter of the insulating gas side bellows 10, so that it is placed in contact with both bellows 9, 10 when the vacuum valve is assembled. .
The buffer material 11 is inserted into the gap formed by deforming and expanding the bellows 10 so that the end plate 13 side of the insulating gas side bellows 10 is slightly pulled out because the buffer material 11 is resinous and easily deformed. Insertion is possible by inserting 11 while deforming.
An end plate 13 is fixed to the insulating gas side bellows 10 on the end surface of the vacuum vessel movable side flange 12 side. As shown in FIG. 2, the end plate 13 seals the cushioning material 11 between the bellows 9 and 10 and then airtightly joins the flange 12. This joining may be performed by welding 32 as shown in FIG. 3 in addition to fastening by screws 30 and packing 31 by forming holes in the end plate 13 and screwing screws 30 into screw holes provided in the flange 12. The airtight space 15 sealed by the end plate 13 and the bellows 9 and 10 is set to a pressure lower than the pressure of the insulating gas.

In the vacuum valve of this form, since the buffer material 11 is present, vibration energy generated in the bellows 9 and 10 when the vacuum valve is opened and closed is absorbed by the buffer material 11 and dissipated. Can be suppressed. That is, the increase in stress of the bellows 9 and 10 accompanying the increase in voltage can be suppressed. Since the cushioning material 11 disposed between the bellows 9 and 10 prevents the bellows 9 and 10 from coming into contact with each other and being damaged, the bellows 9 and 10 can be brought close to each other for miniaturization. After fixing the members other than the cushioning material 11 by vacuum brazing at a high temperature, the cushioning material 11 is inserted between the bellows 9 and 10, and the rear end plate 13 is joined to the movable flange 12 to thereby form the bellows 9 and 10. The space can be made an airtight space. As described above, in the vacuum valve of the present embodiment, a downsized vacuum valve can be obtained.

Embodiment 2. FIG.
FIG. 4 is a cross-sectional view showing the configuration of the vacuum valve according to the second embodiment. In this embodiment, a pleat 16a is attached to one side of the cushioning material 16 as shown in FIG. 3 in the first embodiment, and the crest 16a has a peak diameter equal to or larger than the valley diameter of the vacuum side bellows 9. Is in contact with both bellows 9, 10, and the pleat 16 a enters the valley of the vacuum side bellows 9. FIG. 5 is a perspective view showing the outer shape of the cushioning material 16. In FIG. 4, the pleats 16 a are on the outer diameter side, but the pleats 16 a may be provided on the inner diameter side of the cushioning material 16. When the pleat 16a is provided on the inner side, the crest diameter of the cushioning material 16 is equal to or greater than the trough diameter of the insulating gas side bellows 10. Further, the shape of the pleats 16a may be a saw type other than the circular shape in FIG.

In the vacuum valve of this form, the cushioning material 16 itself has a deformable flexibility. Since the cushioning material 16 that can be enclosed between the bellows 9 and 10 has more surfaces in contact with the bellows 9 and 19, The dissipating action of the vibration energy of the bellows 9 and 10 is increased, and the mechanical opening / closing life of the bellows 9 and 10 is further improved.

Embodiment 3 FIG.
FIG. 6 is a block diagram of a vacuum valve according to the third embodiment. In this embodiment, the top position of the valley of the vacuum side bellows 17 and the bottom position of the peak of the insulating gas side bellows 18 are matched.

In the vacuum valve of this form, the narrowest part is formed at the bottom position of the valley of the vacuum side bellows 17 and the top position of the peak of the insulating gas side bellows 18 in the space that encloses the buffer material 11 between the bellows. Since the cushioning material 11 is pressed against the end surfaces of the bellows 17 and 18, the contact state between the cushioning material 11 and the bellows 17 and 18 is stable, so that the vibration energy dissipation action of the bellows can be stably obtained. . In addition, the cushioning material can be easily pushed in and sealed, and the assembly workability is improved.

Embodiment 4 FIG.
FIG. 7 is a configuration diagram of a vacuum valve according to the fourth embodiment. In this embodiment, the cushioning material 19 has a pleated shape on both sides, the outer diameter side fold diameter is equal to or larger than the valley diameter of the vacuum side bellows 17, and the inner diameter side fold diameter is the insulating gas side bellows. In addition to being in contact with both bellows 17, 18, the cushioning material 19 enters the ridges of the vacuum bellows 17 and the valleys of the insulating gas side bellows 18. Yes.

In the vacuum valve of this form, as in the second embodiment, the cushioning material itself can be enclosed between the bellows by the deformation flexibility of the cushioning material, and the enclosed cushioning material increases the surface in contact with the bellows. This is effective in further improving the mechanical open / close life reliability of the bellows.

Embodiment 5 FIG.
FIG. 8 is a configuration diagram of a vacuum valve according to the fifth embodiment. In this embodiment, the outer diameter of the end plate 20 is smaller than the mountain diameter of the insulating gas side bellows 10, and the end plate 10 and the movable side flange 12 are joined by a disk-shaped plate material 21.

In the vacuum valve of this form, since the outer diameter of the end plate 20 is smaller than the inner diameter of the buffer material 11, the buffer material 11 can be sealed without interfering with the end plate 20 without deforming and damaging the buffer material. As a result, assembly workability is improved.

Embodiment 6 FIG.
FIG. 9 is a configuration diagram of a vacuum valve according to the sixth embodiment. In this embodiment, a cushioning material 22 having no expansion / contraction function is inserted between the vacuum side bellows 9 and the insulating gas side bellows 10, and the length of the cushioning material 22 is shorter than the bellows 9 and 10.
In the vacuum valve of this embodiment, since the cushioning material 22 is not expanded and contracted, the cushioning material 22 does not enter the valley when the bellows 9 and 10 are operated, so that the insertion at the time of assembly becomes easy and the assembly workability is good. Become.

DESCRIPTION OF SYMBOLS 1 Insulation container 2 Fixed side electrode rod 3 Fixed side flange 4 Metal container 5 Fixed side electrode rod 6 Movable side electrode rod 7 Movable side electrode rod 8 Bellows protection shield 9 Vacuum side bellows (first bellows)
10 Insulating gas side bellows (second bellows)
11 Buffer material 12 Vacuum container movable side flange 13 End plate 14 Guide 15 Airtight space 16 Buffer material 16a Fold 17 Vacuum side bellows 18 Insulating gas side bellows 19 Buffer material 20 End plate 21 Plate material 22 Buffer material 30 Screw 31 Packing 33 Welding 100 Vacuum valve

Claims (1)

  A fixed side and a movable side electrode for opening and closing a circuit in the vacuum vessel, an electrode rod that passes through one end of the vacuum vessel to support the movable side electrode and is driven to open and close, and a through-hole of the vacuum vessel in the electrode rod In a vacuum valve comprising an electrode rod and a bellows that is extendable and airtightly connected between the vacuum vessel, the bellows is an airtight space between a first bellows and a second bellows arranged coaxially in parallel. The pressure in the airtight space is set to an intermediate value between the pressure on the outer periphery of the first bellows and the pressure on the inner diameter side of the first bellows, and a cushioning material is disposed in the sealed space. A vacuum valve.

Images